When Fisher was two, her parents divorced after her father left Reynolds for her best friend, actress Elizabeth Taylor, the widow of her father's best friend Mike Todd. The following year, her mother married shoe store chain owner Harry Karl, who secretly spent Reynolds's life savings. She attended Beverly Hills High School, but she left to join her mother on the road.[5] She appeared as a debutante and singer in the hit Broadway revival Irene (1973), which starred her mother.

In 1987, Fisher published her first novel, Postcards from the Edge. The book was semi-autobiographical in the sense that she fictionalized and satirized real-life events such as her drug addiction of the late 1970s and her relationship with her mother. It became a bestseller, and she received the Los Angeles Pen Award for Best First Novel. Also during 1987, she was in the Australian film The Time Guardian. In 1989, Fisher played a major supporting role in When Harry Met Sally, and in the same year, she appeared with Tom Hanks as his wife in The 'Burbs.

Fisher wrote and performed in her one-woman play Wishful Drinking at the Geffen Playhouse in Los Angeles from November 7, 2006, to January 14, 2007.[13] Her show played at the Berkeley Repertory Theater through April 2008,[14] followed by performances in San Jose, California, in July 2008, Hartford Stage in August 2008[15] before moving on to the Arena Stage in Washington, D.C., in September 2008[16] and Boston[17] in October 2008. Fisher published her autobiographical book, also titled Wishful Drinking, based on her successful play in December 2008 and embarked on a media tour. On April 2, 2009, Fisher returned to the stage with her play at the Seattle Repertory Theatre with performances through May 9, 2009.[18] On October 4, 2009, Wishful Drinking then opened on Broadway in New York at Studio 54 and played an extended run until January 17, 2010.[19][20] In December 2009, Fisher's audiobook recording of her best-selling memoir, Wishful Drinking, earned her a nomination for a 2009 Grammy Award in the Best Spoken Word Album category.[21]

Fisher joined Turner Classic Movies host Robert Osborne on Saturday evenings for The Essentials with informative and entertaining conversation on Hollywood's best films. She guest-starred in the episode titled "Sex and Another City" from season 3 of Sex and the City with Sarah Jessica Parker. This episode also featured Vince Vaughn, Hugh Hefner, and Sam Seder in guest roles. On October 25, 2007, Fisher guest-starred as Rosemary Howard on the second season episode of 30 Rock called "Rosemary's Baby", for which she received an Emmy Award[22] nomination. Her last line in the show was a spoof from Star Wars: "Help me Liz Lemon, You're my only hope!" On April 28, 2008, she was a guest on Deal or No Deal. In 2008, she also had a cameo as a doctor in the Star Wars-related comedy Fanboys.

In 2010, HBO aired a feature-length documentary based on a special live performance of Fisher's Wishful Drinking stage production.[23] Fisher also appeared on the seventh season of Entourage in the summer of 2010.[23]

In June 2014, she filmed an appearance on the UK comedy panel show QI. It was broadcast on December 25, 2014.[24] In 2015 she will star alongside Sharon Horgan and American comedian Rob Delaney in Catastrophe, a six-part comedy series for the British Channel 4[25] that will air in the UK from 19 January 2015.

In an interview posted March 2013, Fisher said she would reprise her role as Princess Leia in Episode VII of the series, "Elderly. She’s in an intergalactic old folks’ home [laughs]. I just think she would be just like she was before, only slower and less inclined to be up for the big battle."[26] After other media outlets reported this on March 6, 2013, her representative said the same day Fisher was joking and nothing has been announced.[27]

On January 21, 2014, in an interview with TV Guide, Carrie Fisher confirmed her involvement and the involvement of the original cast in the upcoming sequels by saying "as for the next Star Wars film, myself, Harrison Ford and Mark Hamill are expected to report to work in March or April. I'd like to wear my old cinnamon buns hairstyle again but with white hair. I think that would be funny."[28]

In March 2014, Fisher stated that she was moving to London for six months because that was where filming would take place. She also confirmed she would try to get in better shape for the role.[29]

Fisher dated musician Paul Simon from 1977 until 1983. In 1980 she was briefly engaged to Canadian actor and comedian Dan Aykroyd, who proposed on the set of their film The Blues Brothers. She said: "We had rings, we got blood tests, the whole shot. But then I got back together with Paul Simon."[30] Fisher was married to Simon from August 1983 to July 1984, and they dated again for a time after their divorce. During their marriage, she appeared in Simon's music video for the song "Rene and Georgette Magritte with Their Dog after the War". Simon's song "Hearts and Bones" is about their relationship.[31]

Subsequently, she had a relationship with Creative Artists Agency principal and casting agentBryan Lourd. They had one child together, Billie Catherine Lourd (born July 17, 1992). Eddie Fisher states in his autobiography (Been There Done That) his granddaughter's name is Catherine Fisher Lourd and her nickname is "Billy". The couple's relationship ended when Lourd left to be in a relationship with another man. Though Fisher has described Lourd as her second husband in interviews, according to a 2004 profile of the actress and writer, she and Lourd were never legally married.[32]

Fisher also had a close relationship with James Blunt. While working on his album Back to Bedlam in 2003, Blunt spent much of his time at Fisher's residence. When Vanity Fair's George Wayne asked Fisher if their relationship was sexual, she replied: "Absolutely not, but I did become his therapist. He was a soldier. This boy has seen awful stuff. Every time James hears fireworks or anything like that, his heart beats faster, and he gets 'fight or flight.' You know, he comes from a long line of soldiers dating back to the 10th century. He would tell me these horrible stories. He was a captain, a reconnaissance soldier. I became James’s therapist. So it would have been unethical to sleep with my patient."[6]

On February 26, 2005, R. Gregory "Greg" Stevens, a lobbyist, was found dead in Fisher's California home due to an overdose of OxyContin compounded by obstructive sleep apnea.[33] In an interview, Fisher claimed that Stevens's ghost haunted her mansion, which unsettled her: "I was a nut for a year", she explained, "and in that year I took drugs again."[6]

Fisher has described herself as an "enthusiastic agnostic who would be happy to be shown that there is a God".[34] She was raised Protestant,[2] but often attends Jewish services, the faith of her father, with Orthodox friends.[35] She was a spokesperson for Jenny Craig, Inc. television ads that aired in January 2011.[36]

While she was in Sydney, Australia, Fisher revealed in another interview that she had a cocaine addiction during the filming of The Empire Strikes Back, and also survived an overdose. "Slowly, I realized I was doing a bit more drugs than other people and losing my choice in the matter", she said in an interview.[40][41]